The invention relates to an apparatus for the treatment of particulate material, with a process chamber for the reception and treatment of the material.
An apparatus of this type is known, for example, from DE 100 54 557 A1.
This apparatus is served, in particular for granulating or coating a particulate material. A gaseous medium, what is known as process air, is introduced into the process chamber via the bottom and at the same time flows, directed approximately horizontally, into the process chamber through the numerous orifices, mostly in the form of slots between mutually overlapping guide plates.
In this context, it became known to configure the bottom differently, as is known, for example, from DE 199 04 147 A1, DE 102 02 584 C1 or DE 102 48 116 B3. The material to be treated is swirled by the process air, the swirl characteristic being dependent in each case on the configuration of the bottom. If, for example, a certain circumferential component is also superposed on the process air, a toroidally revolving eddy flow ring is gradually formed.
If larger agglomerates are to be formed from dust-fine powder, say if the material is to be granulated, a tacky medium is supplied to the toroidal ring via nozzles. In DE 102 48 116 C1, for example, these are spray nozzles directed obliquely upward which are inserted in the wall of the container surrounding the process chamber. Where coating is concerned, a covering layer is to be applied, that is to say sprayed, as uniformly as possible onto an already existing larger body.
The material particles swirled by the process air fall down onto the floor again due to gravity, that is to say are separated from the process air which flows out of the process chamber to the upper outflow end via an outlet.
The process air is introduced via an inlet in an inflow chamber arranged below the bottom and then penetrates through the bottom into the process chamber through the numerous orifices.
After leaving the process chamber, if appropriate after flowing through filters arranged at the upper end of the process chamber, the process air is discharged from the apparatus and recycled.
In conventional apparatuses, separate monobloc units are provided, which are arranged in spaces away from the apparatus, mostly next to or above it, and are connected to the apparatus via pipeline systems.
In such instances, supply-air monobloc units are referred to, which are responsible for conditioning the process air, and exhaust-air monobloc units which ensure the environmentally correct disposal of the process exhaust air. The process air supplied is appropriately heated, brought to a specific drying/moisture content and moved into a degree of throughflow suitable for process management.
Depending on the type of treatment of the material, moisture, in particular solvents, must be extracted from the discharged process air.
The known type of interaction between the actual apparatus, that is to say the fluidized bed granulating and coating plant and the necessary supply-air monobloc and exhaust-air monobloc units requires a large amount of space and room. In this case, this often gives rise to long air paths via supply pipes and, as a result of this, to large inner surfaces which have to be cleaned or otherwise maintained from time to time.
Since such apparatuses are in widespread use in the pharmaceutical industry, these lines are produced from high-grade metallic materials which constitute a relatively large metallic mass which is an obstacle to a rapid variation of process air temperatures, since this large mass constitutes an inert system.
Air-routing pipelines can be properly inspected only rarely on their inner surface, and therefore the cleaning of these can be carried out only by means of technically complicated integrated cleaning systems. Cleaning in place or washing in place devices are referred to in this context.
Plant systems where there are gaps also require a relatively high outlay in terms of sound and heat insulation, thus resulting in considerable costs for setting up and operating an apparatus of this type.
U.S. Pat. No. 4,557,904 discloses a reactor for carrying out exothermal chemical reactions, in which a fluidizing medium is used in order to discharge the reaction heat, A cooler is arranged in the apparatus for cooling and absorbing the exothermal reaction heat.
EP 0 282 777 A discloses an apparatus for the combustion of carbon-containing material in a fluidized bed plant, in the process chamber of which is arranged a heat exchanger which serves for cooling and/or heating the gases.
DE 41 41 227 A1 discloses a fluidized bed reactor which is operated under pressure and around the central reaction space of which a plurality of groups of filters are arranged in order to filter out solids.
U.S. Pat. No. 4,145,818 discloses an apparatus for heating of granular material having a process chamber for fluidizing the granular material. Apart from the process chamber an air heater and a condenser are arranged.
The object of the present invention is to improve an apparatus of the type initially mentioned, to the effect that cost-effective process management is possible.